<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <script src="../js/vue.js"></script>
</head>
<body>
    <div id="app">
        {{flag===true?"正确":"错误"}}
        {{num + 1}}
        {{new String(3)}}
        {{a}}
    </div>
</body>
<script>

    var a=1;

    Vue.config.productionTip = false
    var vm = new Vue({
        el:"#app",
        data:{
            flag:true,
            num:1
        }
    })
</script>
</html>